
If she was my girl, and, as she is so close, I think I would forget the Buscopan.
You don't have long to wait now, and you already know that lots of pregnant bitches have been on antibiotics with no adverse affect on pups.
In your position I would just be ready with everything to hand. Much better being prepared, than being caught out! :-)
If it does turn out to be a phantom, I have to admit that I do try to avoid using Galastop if I can get milk to dry up naturally.